金属电缆护套防腐保护层试验

[中文适用范围]： 提供了由挤压外护套组成的保护性覆盖物可能需要的一系列测试，当覆盖物除了保护下面的金属层免受腐蚀之外，还需要实现以下类型 a) 和 b) 的特殊功能时，例如： a) 绝缘护套系统： i) 采用特殊粘合来减少护套损耗，从而在满负载条件下产生护套电压， ii) 电缆护套可以与地隔离，以允许将电压施加到外护套上检查覆盖物的完整性。 b) 非绝缘护套系统： i) 保护底层金属层免受腐蚀，其中金属层的保护特别重要和/或特定金属和电缆环境的组合会引起严重的腐蚀风险。这些测试仅适用于特定条件和使用，而不必针对正常条件和使用进行。相关电缆规范将提供其实施指南。 [外文原描述]： Provides a range of tests which may be required for protective coverings consisting of extruded oversheaths when the coverings, in addition to protecting underlying metallic layers against corrosion, are required to fulfil special functions, for the following types a) and b), such as: a) insulated sheath systems: i) where special bonding is employed to reduce sheath losses, resulting in a sheath voltage under full load conditions, ii) where the cable sheath can be isolated from earth to permit a voltage to be applied to the oversheath to check the integrity of the covering. b) uninsulated sheath system: i) protection against corrosion of the underlying metal layer where preservation of the metal layer is of particular importance and/or the combination of the particular metal and the cable environment would give rise to a serious risk of corrosion. These tests are only appropriate to particular conditions and use, and do not have to be implemented for normal conditions and use. Guidance on their implementation will be provided in the relevant cable specification.